"Flu Vaccine Could Have Far Reach Under Best Circumstances"

Read David Brown's article in The Washington Post.

"Data presented Tuesday at an international conference on bird flu indicate that drug manufacturers could produce enough influenza vaccine starting sometime in 2008 to protect between a quarter and half the world's population over the course of a year, should a new and dangerous strain of flu virus emerge..........

"For a vaccine to reach a quarter to a half of the world's population -- 1.7 billion to 3.4 billion people -- current plans by manufacturers to expand production would have to go forward uninterrupted. In order to immunize the maximum number of people, doses would also have to be used with immunity-boosting substances that would make the vaccine more effective. The projections assume there will be enough trained technicians and needles on hand to administer the vaccines.

"The projection of reaching up to 3.4 billion people also assumes the use of a technique that would double the vaccine's potency, based on research being conducted."

The impact of vaccines would seem to me to depend heavily on the way the vaccine was used. If a quarter of the world population were immunized, emphasizing health care workers and high risk people in relatively affluent countries, it could probably reduce mortality and disease burden in those countries. If the immunizations were allocated preferentially to creating herd immunity in man in areas in which bird flu was likely to jump to human populations then a pandemic might be averted totally.